Faculty Bibliography

RATIONALE/BACKGROUND:Poor adherence to inhaler use can be due to poor temporal and/or technique adherence. Up until now there has been no way of reliably tracking both these factors in everyday inhaler use. OBJECTIVES/OBJECTIVE:This paper introduces a device developed to create time stamped acoustic recordings of an individual's inhaler use, in which empirical evidence of temporal and technique adherence in inhaler use can be monitored over time. The correlation between clinical outcomes and adherence, as determined by this device, was compared for temporal adherence alone and combined temporal and technique adherence. FINDINGS/RESULTS:The technology was validated by showing that the doses taken matched the number of audio recordings (r2 = 0.94, p<0.01). To demonstrate that audio analysis of inhaler use gives objective information, in vitro studies were performed. These showed that acoustic profiles of inhalations correlated with the peak inspiratory flow rate (r2 = 0.97, p<0.01), and that the acoustic energy of exhalations into the inhaler was related to the amount of drug removed. Despite training, 16% of participants exhaled into the mouthpiece after priming, in >20% of their inhaler events. Repeated training reduced this to 7% of participants (p = 0.03). When time of use was considered, there was no evidence of a relationship between adherence and changes in AQLQ (r2 = 0.2) or PEFR (r2 = 0.2). Combining time and technique the rate of adherence was related to changes in AQLQ (r2 = 0.53, p = 0.01) and PEFR (r2 = 0.29, p = 0.01). CONCLUSIONS:This study presents a novel method to objectively assess how errors in both time and technique of inhaler use impact on clinical outcomes. TRIAL REGISTRATION/BACKGROUND:EudraCT 2011-004149-42.

Drug delivery from a Dry Powder Inhaler (DPI) is dependent on the peak inspiratory flow rate (PIFR) generated. Currently available methods for estimating PIFR from most DPIs are limited and mainly rely on subjective assessment. We aim to show that spirometric and Diskusâ„¢ PIFR and Inspiratory Vital Capacity (IVC) are related to the underlying respiratory condition and that spirometric PIFR can be used to assess whether Diskusâ„¢ PIFR will be adequate when using this DPI. Healthy volunteers and patients with asthma, COPD, neuromuscular disease and non-respiratory disorders were recruited (n = 85). Demographics and baseline lung function by spirometry were recorded. Flow and volume readings were taken while patients used a Diskusâ„¢ DPI, housed in an airtight container connected to a spirometer. T-tests were performed to compare mean spirometric and Diskusâ„¢ PIFR/ IVC between groups. Stepwise regression analysis of Diskusâ„¢ PIFR versus spirometric PIFR, spirometric IVC, age, gender, condition, BMI, FEV1 and FVC was performed. The Diskusâ„¢ PIFR for the COPD and Neuromuscular Disease group was more than 10 L/min lower than the Healthy or Asthma groups (p < 0.05). The mean spirometric and Diskusâ„¢ IVC of the Healthy group was significantly (>0.75 L) higher than the mean for the other three groups (p < 0.05). Diskusâ„¢ PIFR was moderately correlated with spirometric PIFR and age (Adjusted R(2) = 0.58, p < 0.0001). PIFR generated using a Diskusâ„¢ DPI is dependent on the underlying disease and age. A spirometric PIFR of less than 196 L/min should prompt further investigation into the suitability of a patient for a Diskusâ„¢ DPI, with possible consideration of alternate devices.

Chronic respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD) affect over 400 million people and are incurable. The pressurized metered dose inhaler (pMDI) has been the most popular inhaler device in inhaled therapy in recent times. However the pMDIs require good coordination between inhaling and actuating the inhaler to deliver the aerosolized drug most effectively. Poor coordination can greatly reduce the amount of drug delivered to a patient and therefore reducing the control of respiratory disease symptoms. Acoustic methods have been recently employed to monitor inhaler technique quite effectively. This study employs a noninvasive acoustic method to detect actuation sounds in a portable monitoring device. A total of 158 actuation sounds were obtained from a group of healthy subjects (n=5) and subjects suffering from respiratory diseases (n=15). The developed algorithm generated an overall accuracy of 99.7% demonstrating that this method may have clinical potential to monitor pMDI actuation coordination. The informative feedback from this method may also be employed in clinical training to highlight patient actuation technique.

BACKGROUND:The implementation of workplace smoking bans has contributed to a significant reduction in the incidence of acute coronary syndrome admissions, but their influence on adult acute pulmonary disease admissions is unclear. We sought to assess the impact of a national smoking ban on nationwide admissions of individuals of working age with acute pulmonary illness. METHODS:Data relating to emergency hospital admissions of subjects aged 20 to 70 years preceding and succeeding the implementation of the Irish smoking ban were obtained from a central registry. Population, weather, pollution, and influenza data were obtained from the relevant authorities. Poisson regression analysis was used to assess adjusted risk of emergency hospital admission following implementation of the smoking ban. RESULTS:Overall admissions with pulmonary illness decreased from 439 per 100,000 population per annum to 396 per 100,000 population per annum following the ban (unadjusted relative risk [RR], 0.91; 95% CI, 0.83-0.99; P = .048). This persisted following adjustment for confounding factors (adjusted RR, 0.85; 95% CI, 0.72-0.99; P = .04) and was most marked among younger age groups and in admissions due to asthma (adjusted RR, 0.60; 95% CI, 0.39-0.91; P = .016). Admissions with acute coronary syndromes (adjusted RR, 0.82; 95% CI, 0.70-0.97; P = .02), but not stroke (adjusted RR, 0.93; 95% CI, 0.73-1.20; P = .60), were also reduced. CONCLUSIONS:The implementation of a nationwide workplace smoking ban is associated with a decline in admissions with acute pulmonary disease among specific age groups and an overall reduction in asthma admissions. This may result from reduced exposure of vulnerable individuals to environmental tobacco smoke, emphasizing the potential benefit of legislation reducing second-hand smoke exposure.